CVE-2022-20837: Cisco IOS XE Software DNS NAT Protocol Application Layer Gateway Denial of Service Vulnerability
First published: Mon Oct 10 2022(Updated: )
A vulnerability in the DNS application layer gateway (ALG) functionality that is used by Network Address Translation (NAT) in Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause an affected device to reload. This vulnerability is due to a logic error that occurs when an affected device inspects certain TCP DNS packets. An attacker could exploit this vulnerability by sending crafted DNS packets through the affected device that is performing NAT for DNS packets. A successful exploit could allow the attacker to cause the device to reload, resulting in a denial of service (DoS) condition on the affected device. Note: This vulnerability can be exploited only by sending IPv4 TCP packets through an affected device. This vulnerability cannot be exploited by sending IPv6 traffic.
Credit: ykramarz@cisco.com
| Affected Software | Affected Version | How to fix |
|---|---|---|
| Cisco IOS XE | ||
| Cisco Asr 1000-esp100-x | ||
| Cisco Asr 1000-esp200-x | ||
| Cisco Catalyst 8500 | ||
| Cisco Catalyst 8500-4qc |
Never miss a vulnerability like this again
Sign up to SecAlerts for real-time vulnerability data matched to your software, aggregated from hundreds of sources.
Reference Links
Frequently Asked Questions
What is CVE-2022-20837?
CVE-2022-20837 is a vulnerability in the DNS application layer gateway (ALG) functionality that is used by Network Address Translation (NAT) in Cisco IOS XE Software, which could allow an unauthenticated, remote attacker to cause an affected device to reload.
What is the severity of CVE-2022-20837?
The severity of CVE-2022-20837 is high with a CVSS score of 8.6.
Which software is affected by CVE-2022-20837?
Cisco IOS XE Software is affected by CVE-2022-20837.
How can CVE-2022-20837 be exploited?
CVE-2022-20837 can be exploited by an unauthenticated, remote attacker.
Is there a fix for CVE-2022-20837?
Please refer to the Cisco Security Advisory for information on available fixes for CVE-2022-20837.
- collector/nvd-index
- agent/type
- agent/softwarecombine
- collector/mitre-cve
- source/MITRE
- agent/references
- agent/last-modified-date
- agent/title
- agent/severity
- agent/author
- agent/weakness
- agent/tags
- agent/description
- agent/first-publish-date
- agent/event
- vendor/cisco
- canonical/cisco ios xe
- canonical/cisco asr 1000-esp100-x
- canonical/cisco asr 1000-esp200-x
- canonical/cisco catalyst 8500
- canonical/cisco catalyst 8500-4qc